1200 sq ft ADU Plan – Permit Ready

A 1200 sq ft two-story two-bedroom ADU that fits full primary-residence livability on a narrow-lot footprint. The layout configures 2 bedrooms and 2 baths within a clean, code-aware envelope. Strong fit for multi-generational households where the floor separation creates real privacy between household zones. The plan includes an upper-floor balcony and a covered porch.

Front 3D isometric rendering of a 1200 sq ft 2-bedroom 2-story ADU plan in California — Exterior rendering of the 1200 sq ft permit-ready ADU plan designed as a detached backyard cottage.

Plan A22-1200 Specifications

Base area	1,200 sq ft
Bedrooms	2 Bedrooms
Bathrooms	2 Bath
Stories	2-Story
Ridge height	20.75 ft
Ceiling height	8.5 ft
Roof slope	4:12
Open porch	88 sq ft
Covered porch	92 sq ft
Balcony	74 sq ft

Code & Engineering

This 1200 sq ft two-story ADU plan with 2 bedrooms and 2 baths is delivered as a permit-ready architectural plan set developed for California parcels under the state's detached ADU regulations (Government Code §65852.2 and §65852.22).

The architectural plan set includes the floor plans for both stories, exterior elevations on all four sides, building sections, and dimensioned framing intent. The design is developed to meet the current California Residential Code (CRC) and is intended for structural design under ASCE 7 for loading and the National Design Specification (NDS) for wood construction.

The Structural Set package is offered as a separate scope and includes lateral analysis, gravity load takedown, shear-wall design, and component-level connection details — all sized to the specific site's seismic and wind conditions rather than to a generic California average.

Foundation design is offered as a separate service so the right system can be selected for each site. Slab-on-grade is typical on stable, level lots; raised crawl-space on continuous stem walls is preferred on parcels with expansive clay or moisture concerns; pier-and-grade-beam systems are generally required on hillside lots, soft-soil regions, or where the geotechnical report calls for deeper bearing.

The plan's 20.75 ft ridge height exceeds California's standard 16-foot detached-ADU limit and the 18-foot transit-served / multifamily-zoned allowance. Several adaptations are available depending on your parcel: plan customization to lower the roof slope or revise the upper-floor elevation so the ridge fits the applicable height limit; configuration as an attached ADU where height matches the primary dwelling up to 25 feet; use as a small single-family residence in a zone permitting two-story construction; or permitting on parcels where local jurisdictional provisions allow greater height for detached secondary units. Plan customization is offered as an optional design service to adapt the plan to a specific parcel.

Optional add-on services include PE-stamped structural calculations, plan customization (roof slope adjustments, elevation revisions, layout modifications), custom foundation design tailored to the soils report, on-site structural observation during construction, and permit support for jurisdictions with non-standard plan-check comments.